1. Field of the Invention
The present invention relates to a hard disk drive, and more particularly, to a balancer for controlling the balance of a head stack assembly (HSA), the HSA having the balance, a method for manufacturing the balancer, and a method for manufacturing an overmold of the HSA.
2. Description of the Related Art
Hard disk drives (HDDs) are auxiliary memory devices used for computers, MP3 players, or mobile phones. The HDD reads or writes data with respect to a disk that is a data storage medium, using a head slider that is a data read/write medium. During the operation of the HDD, the head slider maintains a floating state rising a predetermined distance from the disk and a magnetic head mounted on the head slider reads or writes data with respect to the disk. A device to support the head slider attached on an end portion thereof and moving the same to a predetermined position on the disk is referred to as a head stack assembly (HSA).
The HSA has unbalance due to factors such as allowance in parts or in assembly. The head slider mounted on an end portion of the HSA moves to a particular track as the HSA pivots, and performs reading and writing of data. Unexpected external interference applied to the HDD causes vibrations to the HSA. When a degree of the unbalance of the HSA is great, the vibration of the HSA due to the external interference increases so that a position error signal (PES) characteristic is deteriorated and data processing is delayed or prevented. Thus, a balancing work to reduce the unbalance of the HSA is needed.